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    <script>
        var a = 10;       
         m =  a++ + ++a + a +a++  + a + ++a; 
        //  a++返回a的原值,但是a++的++加1和后面的算式计算       10 + 12 +12 +12 +13+13 =73
         console.log("m = " + m);   //73

    </script>
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